As a professional trainer who helps other people get into shape for a living, it's no surprise Jillian Michaels has an absolutely KILLER body!

But apparently she's not 100% satisfied with her seemingly flawless figure!!

The 39-year-old fitness guru recently opened up about her physique and admitted she think her tush could use a little bit of work! She revealed:

"I've never fully loved my booty. It fits in the clothes nicely. In clothes, I can stuff that sucker into a pair of jeans and you would never know. But out of the jeans it just kinda…falls. And the texture makes me unhappy."

Wow! We always thought she was doing just fine in the donk department!!

Jillian even says she even goes so far as to walk out of bed backwards to hide her rump from her partner Heidi Rhoades!

We find it a bit crazy Jillian would think this considering she's in AH-mazing shape, especially when you consider she's turning 40 next month! But we guess it just goes to show that everybody has their insecurities!

This isn't the first time the 39-year-old's figure has caused controversy. As we reported in January, the American Pie stunner was accused of using Photoshop to make her already narrow waist even smaller.

Reid has admitted to getting plastic surgery in the past to make changes to her abdominal area and breasts -- but the actress asserts that she naturally has a lean shape.